Abstract: The factors which influence the epidemic status were analysised on the base of the surveillance data of HFRS in Jiangsu province 1996.It was suggested that the index of virus carring rats was of the most important indicator.And both the decrease of field accommodation and improvement of living condition in rural area made the epidemic status decrease in some degree as well.The authors suggested that at the present condition,exterminating rat still was the major measure in the control of HFRS,vaccination was only the supplemen-tary measure in the risk area.